Speed -> fatality graphic

[Christian MilNeil]

Sharing this useful graphic, from the Governor’s Highway Safety Association, for folks to share with the City Council and on social media. 

The research behind this graphic was one of the primary motivating factors for Boston and other MA cities to reduce their default speed limits from 30 to 25, with 20 mph safety zones in pedestrian-dense areas. 

 

Christian MilNeil
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[Joey Brunelle]

Christian can you send me the source material for this? I'll post to reddit. But those folks want footnotes. ;-) 

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[Derek Pelletier]

Did folks see this in the NYTimes this week? The videos modeling collision impacts for a pedestrian with either a low profile car or a modern pick-up are harrowing. Glad to see this question addressed by a widespread media source.

The Deadly Rise of Giant Trucks and S.U.V.s - The New York Times 

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[Christian MilNeil]

That's a good question Joey – it came from the Governor’s Highway Safety Association,  but I haven't been able to find the research behind it. 

These might be better graphics to use: they're backed up by a 2011 study from the American Automobile Association (a drivers' lobbying group). Tefft, B.C. (2011). Impact Speed and a Pedestrian’s Risk of Severe Injury or Death (Technical Report). Washington, D.C.: AAA Foundation for Traffic Safety.

It's also basic physics: the kinetic energy of a car increases exponentially with speed according to the equation E=0.5*mass*velocity*velocity. So a car going 40 mph will need to dissipate 4 times as much energy in a crash as the same car going 20 mph. 

Christian MilNeil
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On Wed, Jun 24, 2026 at 11:22 AM Joey Brunelle <joey.b...@gmail.com> wrote:

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